Rotary recording medium having track turns recorded with digital signal and track turns recorded with analog signal

Abstract

A rotary recording medium has information signals recorded on a spiral or concentric tracks formed thereon as variations in geometrical configuration. The tracks comprise a mixture of digital recorded tracks which are recorded with a first modulated signal and analog recorded tracks which are recorded with a second modulated signal. The first modulated signal is a digital signal which has been time-sequentially multiplexed in terms of blocks at a transmission frequency of 44.1 kHz or a frequency extremely close to 44.1 kHz and has then been subjected to a modulation, where each of the blocks are constituted by a synchronizing signal, error correcting codes, and an error detecting code, which are added to a plurality of channels of digital data which are digitally modulated information signals. The second modulated signal is an analog modulated analog information signal at least including a composite video signal. A number of blocks recorded in one track turn of the digital recorded tracks is approximately equal to a product of the transmission frequency and a duration of one revolution of the rotary recording medium.

What is claimed is: 
     
       1. A rotary recording medium having information signals recorded on a spiral track or concentric tracks formed thereon, said spiral track or concentric tracks comprising digital track turns which are recorded with a first modulated signal and analog track turns which are recorded with a second modulated signal, said first modulated signal being a digital signal which comprises modulated time-sequentially multiplexed blocks of digital data, said blocks of digital data being transmitted at a transmission frequence of 44.1 kHz or the transmission frequency extremely close to 44.1 kHz, each of said blocks of digital data comprising a synchronizing signal, error correcting codes, an error detecting code, and digitally modulated information signals of a plurality of channels, said second modulated signal being an analog modulated analog information signal at least including a composite video signal, a number of blocks recorded in one track turn of said digital track turns being approximately equal to a product of said transmission frequency and a duration of one revolution of said rotary recording medium. 
     
     
       2. A rotary recording medium as claimed in claim 1 in which first and second track parts are formed between adjacent digital and analog track turns, said first track part being recorded with a first modulated signal which is a digital modulated signal containing a predetermined data, said second track part being recorded with a second modulated signal which is an analog modulated composite video signal containing an entirely black picture information in video signal durations thereof. 
     
     
       3. A rotary recording medium as claimed in claim 2 in which said track part is formed adjacent to said digital track turn, and said second track part is formed adjacent to said analog track turn. 
     
     
       4. A rotary recording medium having information signals recorded on a spiral track formed thereon as variations in a surface geometry of said rotary recording medium, first and second reference signals having first and second frequencies respectively and being recorded on intermediate parts of said rotary recording medium located between center lines of adjacent track turns so that said first and second reference signals are respectively recorded on the intermediate parts in alternating sequence in a radial direction of said rotary recording medium, said first frequency being different from said second frequency, a third reference signal being recorded at positions where sides on which said first and second reference signals are recorded with respect to one track turn are interchanged, said information signals being reproduced from said rotary recording medium by a reproducing element of a reproducing apparatus which has means for controlling tracking of said reproducing element by an error signal which is obtained by comparing levels of envelopes of said first and second reference signals which are reproduced from said rotary recording medium by said reproducing element, said spiral track comprising digital track turns which are recorded with a first modulated signal and analog track turns which are recorded with a second modulated signal, said first modulated signal being a digital signal which comprises modulated time-sequentially multiplexed blocks of digital data, said blocks of digital data being transmitted at a transmission frequency of 44.1 kHz or the transmission frequency extremely close to 44.1 kHz, each of said blocks of digital data comprising a synchronizing signal, error correcting codes, an error detecting code, and digitally modulated information signals of a plurality of channels, said second modulated signal being an analog modulated analog information signal at least including a composite video signal, a number of blocks recorded in one track turn of said digital track turns being approximately equal to a product of said transmission frequency and a duration of one revolution of said rotary recording medium, said first and second reference signals being recorded at the intermediate part between the center lines of the adjacent track turns in both track turns so that said first and second reference signals are respectively recorded on the intermediate parts in alternating sequence in the radial direction of said rotary recording medium, said third reference signal being recorded on both said digital track turns and said analog track turns for a constant duration at every track turn. 
     
     
       5. A rotary recording medium as claimed in claim 4 in which first and second track parts are formed between adjacent digital and analog track turns, said first track part being recorded with a first modulated signal which is a digital modulated signal containing a predetermined data, said second track part being recorded with a second modulated signal which is an analog modulated composite video signal containing an entirely black picture information in video signal durations thereof. 
     
     
       6. A rotary recording medium as claimed in claim 5 in which said first track part is formed adjacent to said digital track turn, and said second track part is formed adjacent to said analog track turn. 
     
     
       7. A rotary recording medium as claimed in claim 4 in which said composite video signal recorded on said analog track turns has 525 scanning lines and a field frequency of 59.94 Hz or 60 Hz and is recorded at a rate of four fields in one track turn, and said digital signal recorded on said digital track turns has a transmission frequency of 44.056 kHz or the transmission frequency extremely close to 44.056 kHz and is recorded at a rate of 2940 block in one track turn. 
     
     
       8. A rotary recording medium as claimed in claim 4 in which said composite video signal recorded on said analog track turns has 525 scanning lines and a field frequency of 50 Hz and is recorded at a rate of four fields in one track turn, and said digital signal recorded on said digital track turns has a transmission frequency of 44.1 kHz and is recorded at a rate of 3528 blocks in one track turn.